Advent Shadow chronicles the gripping story of Marin Steel, a mercenary pilot thrust into a saga of intergalactic proportions. In the midst of extracting herself from a hostile negotiation, Marin is interrupted by a planetary invasion led by monstrous aliens bent on human genocide. In her efforts to escape the dying world, she encounters young Gideon Wyeth, the unlikely protagonist of Advent Rising, and together they find themselves swept up in a massive struggle against dire forces bent on the destruction of humanity.